C++ Call private / protected function of a common base class

Question

Is there a nice way to call A::foo() from B::bar() in the following sample?

class A {
protected:
  void foo() {}
};

class B : public A {
public:
  void bar(A& a) { // edit: called with &a != this
    a.foo(); // does not work
  }
};

I can't think of anything other than declaring B to be a friend of A, but that could get pretty ugly with some more classes.

Any ideas?

Answer 1

Yes, you can use a base-class function.

class A {
protected:
  void foo() {}
  void do_other_foo(A& ref) {
      ref.foo();
  }
};

class B : public A {
public:
  void bar(A& a) { // edit: called with &a != this
    this->do_other_foo(a);
  }
};